1. Field of the Invention
The present invention relates to an improvement on a fastening structure of a wheel cover, more particularly one, which includes several composite fastening components each consisting of a holding base member, and a fastening piece formed together with the wheel cover body; when several such wheel covers are stacked up, the fastening pieces won't cause increase to the volume of the pile.
2. Brief Description of the Prior Art
Wheels of cars can be made of iron or aluminum alloy. An aluminum alloy wheel doesn't have to be covered with a wheel cover because aluminum alloy wheels have already been made with a pleasant and ornamental look. An iron wheel has to be covered with a wheel cover because the iron wheel isn't very pleasant-looking, and doesn't match the car.
A conventional wheel cover has several fastening parts on an inner side of a main body thereof. The fastening parts each have a convex portion, and the wheel cover is fixed to an iron wheel with the fastening parts being joined to a ringed portion of the iron wheel. Such wheel covers have a drawback: when several wheel covers are stacked up, the fastening parts will cause increase to the volume of the pile. In other words, owing to the fastening parts, when the wheel covers are stacked up, they won't be closely together. Consequently, the pile of wheel covers takes relatively much space, causing increase to the storage and transportation cost.
To overcome the above problem, the inventor of the present invention taught “an improvement on a securing element of a wheel cover”, which was disclosed in U.S. Pat. No. 6,789,854. Referring to FIG. 9, the wheel cover 4 has several connecting projections 41 equidistantly spaced near an edge of an inward side thereof, and securing elements 3 to be fixed to respective ones of the connecting projections 41. Each of the connecting projections 41 has a gap 42 on a middle of an upper end thereof, an engaging hole 44 in the middle, and a bar-shaped portion 43 between the gap 42 and the engaging hole 44. Each securing element 3 has a connecting plate 35, which projects down from a lower end, and which has an engaging block 36 projecting from an inward side and an engaging space 37 formed right above the engaging block 36. The securing elements 3 are joined to respective connecting projections 41 so that the former can be pivoted on the latter between an upright in-use position where the engaging blocks 36 are fitted into the engaging holes 44 and a not-in-use laid down position where the engaging blocks 36 are disengaged from the engaging holes 44 and where the engaging spaces 37 receive the bar-shaped portions 43 therein.
To fix the wheel cover to an iron wheel, first the securing elements 3 are moved to the upright in-use position, and next an iron ring is fitted in the holding trenches 34 of the securing elements 3, and finally the wheel cover is fixed to the iron wheel by means of the convexly curved portions 31 of the securing elements 3. And, when several such wheel covers are stacked up with the securing elements 3 in the laid-down position, the securing elements 3 won't cause increase to the pile, and in turn the wheel covers will be closely together.
The above wheel cover is found to have the following drawbacks: The manufacture has to prepare an additional mold to manufacture the securing elements, and therefore the manufacturing cost is relatively high. And, there is risk of the securing elements being omitted in packaging in the factory/missing in shipment because they come in separate parts before the wheel cover is assembled. Therefore, there is room for improvement.